Connecting; Safety When Connecting Up - Siemens SCALANCE X-300 Series Compact Operating Instructions

Connecting

6.1

Safety when connecting up

Safety notices
When connecting up the device, keep to the safety notices listed below.
The equipment is designed for operation with Safety Extra-Low Voltage (SELV) by a Limited
Power Source (LPS).
This means that only SELV / LPS complying with IEC 60950-1 / EN 60950-1 / VDE 0805-1
must be connected to the power supply terminals, or the power supply unit for the equipment
power supply must comply with NEC Class 2, as described by the National Electrical Code (r)
(ANSI / NFPA 70).
If the equipment is connected to a redundant power supply (two separate power supplies),
both must meet these requirements.
Note
A power source that supplies safety extra low voltage combined with a following NEC Class 2
power limiter also meets the requirements according to IEC 60950‑1 / EN 60950‑1 / VDE
0805‑1 or NEC Class 2. A suitable power limiter is for example the redundancy module SITOP
PSE202U NEC Class 2 (article number 6EP1962-2BA00).
Note
Safety extra-low voltage
The supply of the devices by PELV (Protective Extra Low Voltage) according to DIN VDE
0100-410 or IEC 60364-4-41 is permitted when the generated nominal voltage does not exceed
the voltage limits 25 VAC or 60 VDC.
SCALANCE X-300
Compact Operating Instructions, 11/2019, A5E00982643-18
WARNING
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